For the hardware, it also supports an I/O expansion bus. The I/O expansion bus can be used to implement various I/O functions such as D/I, D/O, A/D, D/A, Timer/Counter, UART, flash memory, battery backup SRAM, ASIC key & other I/O functions. Nearly all kinds of I/O functions can be implemented by this bus but the bus can support only one board. There are more than 50 boards available for μPAC-7186EX, you can choose one of them to expand hardware features.